:: deftheorem Def4 defines (#) VFUNCT_1:def 4 :
for C being non empty set
for V being non empty RLSStruct
for f being PartFunc of C,V
for r being Real
for b₅ being PartFunc of C,V holds
( b₅ = r (#) f iff ( dom b₅ = dom f & ( for c being Element of C st c in dom b₅ holds
b₅ /. c = r * (f /. c) ) ) );